to buy clothes from a wholesale in China, what are things needed for me to get there?

Diona, you should apply for a M type for your visit. The CVASC branch will be open from March 18, 2015. If you apply after March 18, you'd better apply for the M type from the CVASC center. It is located on 14th Floor, Sandton City Office Tower, Corner Rivonia Road & 5th Street, Sandton, 2196. The opening hours are from 09:00 to 15:00 for application service (Monday to Friday).

In order to apply for the M type, you should prepare the following documents:
1. passport valid at least six months and with at least two blank pages
2. completed application form
3. a recent passport photo
4. invitation letter from the wholesale seller
5. invitation letter from duly authorized unit (if necessary). The wholesale seller can help you acquire this from the foreign affairs office
6. financial proof, round-trip trip air tickets and hotel reservation (if necessary)
7. original and copy of your valid resident permit in SA

It usually takes around 4 working days to deal with your application.